<template>
  <div>
     <div>expose: {{num}}</div>
     <a-button @click="changeNum">加</a-button>
  </div>
</template>
<script setup lang="ts">
import { ref } from 'vue'
const num = ref(0)
const changeNum = () => {
  num.value = Math.random()
}
</script>
